Golf tee

ABSTRACT

A molded golf tee prepared by molding a molding material composed of sand and at least a predetermined quantity of binder in a mold, the molded golf tee having a concave hollow portion with a predetermined depth from an upper end, is provided. According to this, when the golf tee is hit with a club for hitting a ball, the golf tee including a concave hollow portion breaks into pieces, so that resistance (impact pressure) is reduced when the golf tee is hit with the club.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a golf tee molded from sand witha mold.

[0003] 2. Description of the Related Art

[0004] Conventionally, typical golf tees used in golf are molded frominexpensive, lightweight plastic materials. However, when plastic golftees are left on golf courses, the shapes thereof remain unchanged.Therefore, the golf tees must be recovered. When the golf tees are notrecovered, they may adversely affect the natural environment. Forexample, birds may swallow them. Golf tees molded from soil as a moldingmaterial are also disclosed in, for example, Japanese Unexamined UtilityModel Registration Application Publication No. 62(1987)-183870 andJapanese Unexamined Patent Application Publication No. 3(1991)-254768.The former discloses a golf tee formed by solid molding using agranular, powdered material, such as soil, in order that a receivingportion thereof has strength adequate for supporting a ball during use,and weathering proceeds speedily by rainwater, sunlight, etc., afterusing. The latter discloses a golf tee formed into the shape of a tee bymixing and integrating 10% to 60% by weight of charcoal, 5% to 30% byweight of fertilizer, the remainder composed of soil, and an appropriatequantity of shaping accelerator for shaping them. Since the golf teesusing soil use materials existing inherently in the natural environment,that is, materials constituting the ground, recovery is not required,and the problem of birds swallowing golf tees does not occur.

[0005] However, since a golf tee using soil or sand, especially sandwhich is an aggregate of granular materials, is unlikely to have areduced thickness, the golf tee must be molded into a massive shape as awhole, and therefore, the weight thereof becomes significantly largerthan that of a plastic material. As a result, in particular, resistancebecomes large when the golf tee is hit with a club when hitting a ball,so that the carry of the ball is decreased, and in addition, there aredisadvantages from the viewpoint of portability and cost reduction.

SUMMARY OF THE INVENTION

[0006] It is an object of the present invention to provide a golf teecapable of increasing the carry of a ball by reducing resistance whenthe golf tee is hit with a club.

[0007] It is another object of the present invention to provide a golftee capable of further improving portability and cost reduction bydecreasing the amount of molding material required.

[0008] In order to achieve the aforementioned objects, according to anaspect of the present invention, a molded golf tee prepared by molding amolding material composed of sand and at least a predetermined quantityof binder in a mold, the molded golf tee having a concave hollow portionwith a predetermined depth from an upper end, is provided. According tothis, when the golf tee is hit with a club for hitting a ball, the golftee including the concave hollow portion breaks into pieces, so thatresistance is reduced when the golf tee is hit with the club.Preferably, the depth of the concave hollow portion is specified to beone-third or more of the total longitudinal length.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is a vertical sectional view of a golf tee according to apreferred embodiment of the present invention.

[0010]FIG. 2 is a plan view of the golf tee shown in FIG. 1.

[0011]FIG. 3 is a vertical sectional view of a golf tee molding machineused for manufacturing the golf tee shown in FIG. 1.

[0012]FIG. 4 is a diagram illustrating use (action) of the golf teeshown in FIG. 1.

[0013]FIG. 5 is a vertical sectional side view of a golf tee accordingto another preferred embodiment of the present invention.

[0014]FIG. 6 is a plan view of the golf tee shown in FIG. 5.

[0015]FIG. 7 is a diagram illustrating use (action) of the golf teeshown in FIG. 5, including a front view thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The preferred embodiments according to the present invention willbe described in detail with reference to the drawings. The attacheddrawings do not limit the present invention, but are provided to makethe present invention easily understandable. In order to avoid acomplicated description of the present invention, detailed explanationsof known portions will not be provided.

[0017] The configuration of a golf tee T according to the presentembodiment will be described with reference to FIG. 1 and FIG. 2.

[0018] The golf tee T is composed of a molded material integrally moldedfrom a molding material M in which at least a predetermined quantity ofbinder C is added to sand S. As the binder C, for example, a phenolicresin or other thermosetting curing agent capable of consolidating thesand S may be used. As this type of binder C, other curing agents may beused, and in addition, additives for further enhancing the consolidationeffect may be used. Biodegradable resins (biodegradable plastics) mayalso be used. The biodegradable resins are naturally decomposed evenwhen left outdoors, and are converted into low-molecular-weightcompounds. Therefore, when the environment is taken into consideration,the biodegradable resins are more preferable materials. On the otherhand, core sand (silica sand) used in the manufacture of a hollowportion during casting may be used as the sand S.

[0019] This golf tee T is composed of a lower-half portion Td formedinto the shape of a cylinder and an upper-half portion Tu graduallyincreasing in diameter upwardly (in the shape of an inverted circularcone) from an upper end of the lower-half portion Td. The lower end ofthe lower-half portion Td is formed into a pointed shape (the shape ofan inverted circular cone). Furthermore, a concave hollow portion Twhaving a predetermined depth from an upper end (upper end surface) Tp ofthe upper-half portion Tu is arranged inside the golf tee T. As shown inFIG. 1, the depth Lw of this concave hollow portion Tw is preferablyspecified to be one-third or more of the total longitudinal length L. Inthe embodiment, the concave hollow portion Tw occupies all of theupper-half portion Tu and a part of the lower-half portion Td. Accordingto this, the upper-half portion Tu is formed into the shape of a cup bya wall portion Wt of about 1 mm thickness. Desirably, the thickness ofthe wall portion Wt is specified to be in the order of 0.7 to 2 mm inconsideration of ensuring satisfactory strength and ease of breakageduring use (hitting the ball).

[0020] A method for manufacturing the golf tee T according to thepresent embodiment will be described with reference to FIG. 3.

[0021]FIG. 3 shows a golf tee molding machine 10. This golf tee moldingmachine 10 is provided with a mold portion 11 and a material blowingdevice 12. The mold portion 11 is composed of an upper mold 11 u and alower mold 11 d, and on the opposing face (parting face), a cavity(mold) X in the shape of the golf tee is arranged. In this case, asshown in FIG. 3, regarding the cavity (mold) X, a shape of only an outerhull of the golf tee is formed and no core portion for forming theaforementioned concave hollow portion Tw exists.

[0022] On the other hand, the material blowing device 12 includes a tank14 for storing the molding material M, and compressed air A can besupplied through a duct 15 to this tank 14 from above. The moldingmaterial M stored in the tank 14 is composed of the sand S containing apredetermined quantity of the binder C as described above.

[0023] When a phenolic resin, for example, which does no harm to theenvironment is used as the binder C, it is essential that in the orderof 1.5% to 2.0% by weight of phenolic resin is mixed relative to thesand S. The usage of the phenolic resin may be reduced to the order of0.7% to 1.3% by weight, and the binding force may be increased by anadhesive, secondary treatment, etc. Regarding the secondary treatment,the golf tee T after molding may be coated with a plant-derivedsecondary curing agent. For example, when the golf tee T after moldingis immersed in and thereby coated with a mucilage in which an agarpowder and a glutinous rice powder are dissolved into a solution,followed by subsequent drying, the binding force can be increased by alarge degree. When a food colorant is added to this mucilage, coloringcan be performed simultaneously. Regarding the adhesive, about 0.5% to3.0% by weight of rice bran may be added relative to the phenolic resin.According to this, when the golf tee T is left sanding on the groundafter using, rainwater, etc., penetrates into the rice bran, andthereby, the breakdown property of the golf tee T left on the ground canbe enhanced. By mixing the binder C and the sand S, the molding materialM in which the binder C is adhered to the surface of the sand S can beproduced. In this case, the molding material M apparently produces afeeling similar to that of dry sand.

[0024] On the other hand, the bottom portion of the tank 14 and thecavity X communicate with each other through a blow hole 16. An outlet15 o of the duct 15 and an inlet 16 i of the blow hole 16 communicatewith each other through a bypass tube 17 for passing through part of thecompressed air A supplied from the duct 15. The bypass tube 17 isspecified to have a diameter which does not interfere with blowing ofthe molding material M into the blow hole 16.

[0025] Consequently, the compressed air A is supplied into the tank 14through the duct 15 during molding, and the molding material M ispressured at an applied pressure in the order of 1 atmosphere (0.01 Pa)for 0.5 to 0.6 sec. According to this, the cavity X is filled with themolding material M. At this time, molding is essentially performed by acore molding technology. In addition, a part of the compressed air A inthe duct 15 directly reaches the blow hole 16 through the bypass tube17, and thereby achieves the blowing of the molding material M.According to this, even with a relatively small cavity X, the moldingmaterial M can effectively be filled into all parts of the cavity X.

[0026] Immediately after a pressuring time lapse of 0.5 to 0.6 sec, asdescribed above, the application of pressure is released, and atreatment for removing any non-adhering molding material M from thecavity X is performed. In this case, when the cavity X is filled withthe molding material M, since the inside of the cavity X has been heatedto a high temperature, adhesion of the molding material M in the cavityX proceeds from the surface side with time. Consequently, when thetreatment for removing the non-adhering molding material M from thecavity X is performed after a lapse of a predetermined time after thecavity X is filled with the molding material M, the non-adhering moldingmaterial M present inside the molded material M (golf tee) is dischargedto the outside, and thereby, the concave hollow portion Tw can beproduced. Regarding the treatment for removing the non-adhering moldingmaterial M from the cavity X, in the case shown in FIG. 3, the treatmentcan be performed by applying a negative pressure, and in the case wherea molding machine is the vertically reverse equivalent of the golf teemolding machine 10 shown in FIG. 3, the non-adhering molding material Mcan be removed based on free fall by releasing the supply of thecompressed air A, and performing an operation of so-called air release.As a result, the golf tee T shown in FIG. 1 can be produced.

[0027] A method for using the golf tee according to the presentembodiment will be described with reference to FIG. 4.

[0028] The method for using the golf tee T is basically the same as thatof a regular golf tee, and therefore, the golf tee T is used while thelower-half portion Td is inserted into the ground E as shown in FIG. 4.Subsequently, a ball B is placed on the upper end of the golf tee T,that is, the upper end Tp of the upper-half portion Tu, and the ball Bis hit with a wood 31 (club).

[0029] When the golf tee T is hit with the wood 31, the upper-halfportion Tu in particular breaks into pieces. That is, since the concavehollow portion Tw and the thin wall portion Wt are provided, theupper-half portion Tu breaks with ease after being hit with the wood 31.FIG. 4 shows the condition in which the upper-half portion Tu hasbroken. As a result, resistance (impact pressure) at the time of hittinga ball B with the wood 31 is reduced by about 15% on an average basiscompared with that of golf tees formed from rigid materials, forexample, plastic, and the following results were attained.

[0030] (a) When the ball B is hit at the position offset from the centerof the wood 31 toward the tip side (the side farther from a player) by 2to 3 cm, in the case of a conventional golf tee formed from a rigidmaterial, for example, plastic, since resistance when the golf tee ishit with the wood 31 is relatively increased, the wood 31 is slightlyrotated about the golf tee, and thereby, a tendency to curve the ballrightward is brought about. However, regarding the golf tee T accordingto the present embodiment, the influence of the position at which theball B is hit with the wood 31 is reduced, and therefore, precisedirectional control can be achieved. Consequently, the golf tee T isespecially suitable for beginners.

[0031] (b) Since the resistance (impact pressure) when the ball B is hitwith the wood 31 is decreased, the carry of the ball B can be increased.

[0032] In particular, the improvement effect of the aforementioned (a)is significant, and this improvement effect is increased with anincrease in the hardness of the ground. The degree of breakage of theupper-half portion Tu can be controlled by selection of the diameter ofthe concave hollow portion Tw (thickness of the wall portion Wt), andalso be controlled by the pressure of the compressed air A duringmolding, the sort of binder C, the ratio of binder C relative to thesand S, mixing of other additives, etc. Since the concave hollow portionTw is provided in the golf tee T, the amount of molding material Mrequired is reduced correspondingly, and portability and cost reductioncan be improved.

[0033] Next, a golf tee Ts according to a modified embodiment of thepresent invention will be described with reference to FIG. 5 to FIG. 7.

[0034] The golf tee T shown in FIG. 1 and FIG. 2 (FIG. 4) is effectivefor increasing the carry of the ball B when hit with the wood 31. On theother hand, the golf tee Ts shown in FIG. 5 to FIG. 7 can achieveexcellent control of the ball B when hit with an iron 32 (FIG. 7).

[0035] As shown in FIG. 5 and FIG. 6, this golf tee Ts includes a mainbody Tum, the total shape thereof being specified to have nearly thesame shape and size as those of the upper-half portion Tu of theaforementioned golf tee T. Consequently, the main body Tum correspondsto the upper-half portion Tu of the aforementioned golf tee T exceptthat the lower end is formed into a pointed shape (the shape of aninverted circular cone). Therefore, the concave hollow portion Tw isarranged throughout the golf tee Ts.

[0036] Furthermore, guide portions Tg and Tg for supporting the ball Band guiding the ball B in a hitting direction Ds are arranged integrallyat the upper end Tp of the main body Tum. A pair of guide portions Tgand Tg are arranged on the right and left sides of the hitting directionDs. The guide portions Tg and Tg are arranged in the shape of parallelrails for supporting the ball B, and the top surfaces of the guideportions Tg and Tg projecting from the upper end Tp constitute ballplacement surfaces Tgr and Tgr. As shown in FIG. 5, the ball placementsurfaces Tgr and Tgr are formed into curved surfaces having intermediateportions slightly dented downward, and in addition, the front end in thehitting direction is located at a position higher than that of the rearend. The other configurations, manufacturing method, etc., are the sameas those of the aforementioned golf tee T. Therefore, in FIG. 5 to FIG.7, the same portions as those in FIG. 1 to FIG. 4 are indicated by thesame reference numerals in order to clarify the configuration, anddetailed explanations thereof will not be provided.

[0037] As shown in FIG. 7, the golf tee Ts is used while the lowerportion thereof is inserted into ground E in a manner similar to that ofa regular golf tee. Subsequently, the ball B is placed on the ballplacement surfaces Tgr and Tgr which are the upper end Tp of the golftee Ts, and the ball B is hit with an iron 32 (club). When the golf teeTs is hit with the iron 32, since the concave hollow portion Tw and thethin wall portion Wt are provided, the golf tee Ts breaks into pieces ina manner similar to that of the golf tee T. In addition, since the guideportions Tg and Tg are provided on the golf tee Ts, the hittingdirection Ds is controlled (guided) by the guide portions Tg and Tg whenthe ball B is hit. That is, the horizontal direction of hittingdirection Ds is controlled by the guide portions Tg and Tg arranged inthe shape of parallel rails, and in addition, the vertical direction(vertical angle) of the hitting direction Ds is controlled by the curvedball placement surfaces Tgr and Tgr.

[0038] The embodiments were described above in detail. However, thepresent invention is not limited to these embodiments, and regarding thedetailed configurations, shapes, materials, numerical values,manufacturing methods, etc., arbitrary changes can be performed withinthe scope and spirit of the present invention, and furthermore, anyaddition or deletion can be performed, if necessary.

What is claimed is:
 1. A molded golf tee prepared by molding a moldingmaterial comprising sand and at least a predetermined quantity of binderin a mold, the molded golf tee having a concave hollow portion with apredetermined depth from an upper end.
 2. The golf tee according toclaim 1, wherein core sand in the manufacture of a hollow portion duringcasting is used for the sand.
 3. The golf tee according to claim 1,wherein a phenolic resin or other thermosetting curing agent is used forthe binder.
 4. The golf tee according to claim 1, wherein abiodegradable plastic is used for the binder.
 5. The golf tee accordingto claim 1, wherein a heated cavity having a shape of only an outer hullof the golf tee is filled with the molding material at a predeterminedapplied pressure for a predetermined time, and thereafter, anon-adhering molding material is removed from the cavity in order tomold the golf tee.
 6. The golf tee according to claim 5, wherein blowingof the molding material into the cavity to be filled therewith isachieved by compressed air passing through a bypass tube.
 7. The golftee according to claim 1, wherein the depth of the concave hollowportion is specified to be one-third or more of the total longitudinallength.
 8. The golf tee according to claim 1, wherein guide portions forsupporting a ball and guiding the ball in a hitting direction areprovided integrally at the upper end.